Component description

The component redirects any domain example.com to www.example.com for HTTP and HTTPS. The reason for that is a limitation in the DNS standard (RFC1033), because of which one cannot point an A record directly to the CNAME of an AWS Load Balancer. In addition the component supports the redirection of subdomains to a directory structure e.g. sub1.example.com to www.exaample.co/sub1.

When to use the Redirect Service?

If you want to point a second-level domain name, e.g. "example.com" to your root360 environment, you cannot simply point an A record to a public IP of your root360 environment. Root360 environments are accessed through elastic loadbalancers that do not have stable IPs. Instead, they have stable domain names which point to a set of changing IPs to enable cross-availability-zone redundancy.

You cannot point an A record to the load balancer's domain. However, you can point a CNAME record to the load balancer domain and this is how we ask you to connect your third-level domains (such as www.example.com) to the loadbalancer. Second-level domains cannot use a CNAME record in this scenario (see below for a technical explanation).

We solve this issue by providing a redirect service that performs http(s)-based redirects to one of your third-level domains which in turn points via CNAME to the load balancer.

To use this service, create an A record that points from your second-level domain to our redirect service. See below for a detailed explanation.

Example

A website is hosted at www.example.com. The dispatch of newsletters and purchase confirmations is made via eg "buchung@example.com". In addition, newsletters and the website contain elements that do not use the fully-qualified domain www.example.com, but it is linked e.g. example.com/schoenes-bild.jpg.

There are now two problems. If example.com is set as CNAME to the AWS load balancer, mail is no longer working. If example.com is set as an A-Record to one of the load balancer IPs, AWS may change the IP of their load balancer at any time an the DNS entry will be obsolete.

The solution is:

• For www.example.com, set a CNAME with the domain name of the loadbalancer

• Redirect example.com using our Redirect Service by pointing it to an A record to our redirect service (52.29.127.0). The service will then redirect any http(s) requests to www.example.com

• (Optional) always fully-qualified domains

Features

• Redirect any domain example.com to www.example.com for HTTP.  HTTPS works automatically because we provide a SSL certificate using letsencrypt (AWS SSL Certificates issued by Amazon are unfortunately not available).

• Specific redirections from subdomains to the directory structure eg specialties.feinkost.de after www.feinkost.de/spezialitäten . This configuration requires configuration by root360. 

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